Share 'Evolve, Episode 9: Speed (History Channel)'

The ability to react and move can often mean the difference between life and death in the animal kingdom. Some animals have evolved into championship fliers, swimmers, and runners. What are the forces that create this need for speed, and how do animal bodies adapt to go into overdrive? In this episode, find out about nature's ultimate engine, muscle, how it evolved and how it works. Meet some of…